CN220271887U

CN220271887U - Quantum random number generator

Info

Publication number: CN220271887U
Application number: CN202322332610.9U
Authority: CN
Inventors: 陈切春; 刘鹏
Original assignee: Shirong Energy Technology Co ltd
Current assignee: Shirong Energy Technology Co ltd
Priority date: 2023-08-29
Filing date: 2023-08-29
Publication date: 2023-12-29
Anticipated expiration: 2033-08-29

Abstract

The application discloses a quantum random number generator, which comprises a light source, a beam splitter, a plurality of photoelectric detectors, a first signal amplifier, a second signal amplifier, a switching module, an analog-to-digital converter and a processor which are connected in sequence; the incidence end of the beam splitter is connected with the light source, the beam splitter is used for dividing the light signals emitted by the light source into multiple paths, and the multiple photoelectric detectors are in one-to-one correspondence with the multiple paths of light signals; the switching module comprises a switch and a second-stage amplifying circuit, wherein the input end of the switch is connected with the output end of the second signal amplifier, the input end of the second-stage amplifying circuit is connected with the first output end of the switch, the output end of the second-stage amplifying circuit is connected with the input end of the analog-to-digital converter, the second output end of the switch is connected with the input end of the analog-to-digital converter, and the switching module is used for switching and conducting the input end of the switch between the first output end and the second output end of the switch.

Description

Quantum random number generator

Technical Field

The application relates to the technical field of quantum random numbers, in particular to a quantum random number generator.

Background

Random numbers are an important underlying resource in the information age. The quantum random number generator generates true random numbers with intrinsic randomness based on a quantum physical principle, and provides great assistance for the fields of scientific simulation, cryptography and the like.

The current quantum random number generator is mainly formed by combining a laser, a beam splitter, a photoelectric detector, a signal amplifier, an analog-to-digital converter and a processor. The beam splitter divides the optical signal emitted by the laser into multiple paths, the photoelectric detector converts the optical signal into a current signal, the signal amplifier amplifies the current signal output by the photoelectric detector and converts the current signal into a voltage signal, the analog-to-digital converter collects the voltage signal output by the signal amplifier, and the processor processes the digital signal output by the analog-to-digital converter to output a random number. However, the current quantum random number generator has the problem of poor system stability when in use.

Disclosure of Invention

To overcome the problems in the related art, the present disclosure provides a quantum random number generator.

The application provides a quantum random number generator, which comprises a light source, a beam splitter, a plurality of photoelectric detectors, a first signal amplifier, a second signal amplifier, a switching module, an analog-to-digital converter and a processor which are sequentially connected; the incident end of the beam splitter is connected with the light source, the beam splitter is used for dividing the light signals emitted by the light source into multiple paths, the multiple photoelectric detectors are in one-to-one correspondence with the multiple paths of light signals, the photoelectric detectors are used for generating current signals from the light signals, the first signal amplifier is used for converting the current signals into voltage signals and amplifying the voltage signals, the second signal amplifier is used for amplifying the voltage signals output by the first signal amplifier, the analog-to-digital converter is used for generating digital signals according to the amplified voltage signals, and the processor is used for generating quantum random numbers according to the digital signals;

the switching module comprises a switching switch and a second-stage amplifying circuit, wherein the input end of the switching switch is connected with the output end of the second signal amplifier, the input end of the second-stage amplifying circuit is connected with the first output end of the switching switch, the output end of the second-stage amplifying circuit is connected with the input end of the analog-to-digital converter, the second output end of the switching switch is connected with the input end of the analog-to-digital converter, and the switching module is used for switching the input end of the switching switch between the first output end and the second output end of the switching switch.

In some embodiments of the present application, the second-stage amplifying circuit includes a first operational amplifier chip, an input end of the first operational amplifier chip is connected to a first output end of the switch, and an output end of the first operational amplifier chip is connected to an input end of the analog-to-digital converter.

In some embodiments of the present application, the quantum random number generator further comprises: the voltage sensor is connected to the output end of the second signal amplifier and is used for detecting the magnitude of a voltage signal output by the second signal amplifier; and the controller is configured to control the output end of the switching switch to be switched according to the detection result of the voltage sensor.

In some embodiments of the present application, the plurality of photodetectors are all avalanche photodiodes.

In some embodiments of the present application, the plurality of photodetectors are arranged in series to form a photodetection circuit, and the first signal amplifier includes: the input end of the I-V conversion circuit is connected with the output end of the photoelectric detection circuit, the output end of the I-V conversion circuit is connected with the input end of the second signal amplifier, and the I-V conversion circuit is used for converting the current signal into a voltage signal and amplifying the voltage signal; and the automatic zero setting circuit is used for integrating the output signal of the I-V conversion circuit, extracting the direct current component in the output signal of the I-V conversion circuit and feeding back the direct current component to the non-inverting input end of the I-V conversion circuit.

In some embodiments of the present application, the auto-zeroing circuit includes a second operational amplifier chip, a capacitor, a first resistor and a second resistor, two ends of the capacitor are respectively connected with an inverting input end and an output end of the second operational amplifier chip, a normal phase input end of the second operational amplifier chip is grounded, an output end of the second operational amplifier chip is connected in series with the first resistor and then connected with a normal phase input end of the I-V conversion circuit, and an inverting input end of the second operational amplifier chip is connected in series with the second resistor and then connected with an output end of the I-V conversion circuit.

In some embodiments of the present application, the I-V conversion includes a third operational amplifier chip, a third resistor and a fourth resistor, two ends of the third resistor are respectively connected with an inverting input end and an output end of the third operational amplifier chip, the inverting input end of the third operational amplifier chip is connected with an output end of the photoelectric detection circuit, a non-inverting input end of the third operational amplifier chip is connected with a first end of the fourth resistor, and a second end of the fourth resistor is grounded.

In some embodiments of the present application, the second signal amplifier includes a first-stage amplifying circuit, an input end of the first-stage amplifying circuit is connected to an output end of the I-V conversion circuit, and an output end of the first-stage amplifying circuit is connected to an input end of the switch.

In some embodiments of the present application, the first-stage amplifying circuit includes a fourth operational amplifier chip, a fifth resistor, a sixth resistor and a seventh resistor, where the fifth resistor is serially connected between the output end of the I-V conversion circuit and the inverting input end of the fourth operational amplifier chip, two ends of the sixth resistor are respectively connected with the inverting input end and the output end of the fourth operational amplifier chip, and the non-inverting input end of the fourth operational amplifier chip is serially connected with the seventh resistor and then grounded.

In some embodiments of the present application, the beam splitter divides the optical signal sent by the light source into two paths, the plurality of photodetectors include a first photodetector and a second photodetector that are arranged in series, a negative electrode of the first photodetector is connected with a positive voltage, a positive electrode of the first photodetector is connected with an input end of the I-V conversion circuit, a positive electrode of the second photodetector is connected with a negative voltage, and a negative electrode of the second photodetector is connected with a positive electrode of the first photodetector.

The quantum random number generator provided by the application can realize the following beneficial technical effects:

the quantum random number generator provided by the application is provided with a first signal amplifier and a second signal amplifier, a switching module is arranged behind the second signal amplifier and comprises a switch and a second-stage amplifying circuit, the input end of the switch can be respectively switched and conducted with the first output end and the second output end of the switch according to actual requirements, and when the input end of the switch is conducted with the first output end of the switch, a voltage signal can be amplified again through the second-stage amplifying circuit by the switching module, so that the normal conversion of an analog-to-digital converter is ensured. When the switching module conducts the input end of the switching switch with the second output end of the switching switch, the voltage signal output from the second signal amplifier can directly enter the input end of the analog-to-digital converter, and the voltage signal does not need to be amplified again. By the design, the compatibility of the light source intensity is improved, the voltage signal input to the analog-to-digital converter is ensured to meet the signal use requirement, meanwhile, the saturation of the voltage signal is avoided, and therefore the system stability of the quantum random number generator can be effectively improved.

Other characteristic features and advantages of the present application will become apparent from the following description of exemplary embodiments, which is to be read with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application. In the drawings, like reference numerals are used to identify like elements. The drawings, which are included in the description below, are some, but not all embodiments of the present application. Other figures can be derived from these figures by one of ordinary skill in the art without undue effort.

FIG. 1 is a schematic diagram of a quantum random number generator shown according to an exemplary embodiment;

fig. 2 is a schematic circuit configuration diagram of a quantum random number generator shown according to an exemplary embodiment.

Reference numerals:

1. a light source; 2. a beam splitter; 3. a photodetector; 31. a photoelectric detection circuit; 4. a first signal amplifier; 41. an I-V conversion circuit; 42. an automatic zero setting circuit; 5. a second signal amplifier; 51. a first-stage amplifying circuit; 6. a switching module; 61. a change-over switch; 62. a controller; 7. an analog-to-digital converter; 8. a processor.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure. It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be arbitrarily combined with each other.

The current quantum random number generator is mainly formed by combining a laser, a beam splitter, a photoelectric detector, a signal amplifier, an analog-to-digital converter and a processor. The beam splitter divides the optical signal that the laser sent into the multichannel, and photoelectric detector converts optical signal into current signal, and signal amplifier amplifies the current signal that photoelectric detector output, and converts into voltage signal, and when light source intensity was weaker, photoelectric detector catches the optical signal intensity weaker, and then leads to the voltage signal intensity that converts out weaker, in order to guarantee that the voltage signal that inputs to analog-to-digital converter has suitable bandwidth and frequency spectrum, need carry out multiple amplification to the voltage signal that intensity is weaker. At least three signal amplifiers are commonly used in the prior art to amplify a voltage signal in multiple stages. However, when the light source intensity is strong, the light signal intensity captured by the photoelectric detector is strong, and then the converted voltage signal intensity is also strong, if the voltage signal with the high intensity is amplified for at least three times, saturation of the voltage signal is easily caused, so that output signal distortion is caused, damage to a signal amplifier is caused, and the system stability of the quantum random number generator is also affected.

In order to solve the above problems, the present application provides a quantum random number generator in which only two signal amplifiers, namely, a first signal amplifier and a second signal amplifier, are required to be provided, so that the number of signal amplifiers is reduced, and the energy consumption is effectively reduced. The switching module is arranged behind the second signal amplifier and comprises a switching switch and a secondary amplifying circuit, the switching module can switch and conduct the input end of the switching switch with the first output end and the second output end of the switching switch respectively according to actual requirements, and when the switching module conducts the input end of the switching switch with the first output end of the switching switch, the voltage signal can be amplified again through the secondary amplifying circuit, so that the normal conversion of the analog-to-digital converter is ensured. When the switching module conducts the input end of the switching switch with the second output end of the switching switch, the voltage signal output from the second signal amplifier can directly enter the input end of the analog-to-digital converter, and the voltage signal does not need to be amplified again. By the design, the compatibility of the light source intensity is improved, the voltage signal input to the analog-to-digital converter is ensured to meet the signal use requirement, meanwhile, the saturation of the voltage signal is avoided, and therefore the system stability of the quantum random number generator can be effectively improved.

The quantum random number generator provided according to the present application will be described in detail with reference to the accompanying drawings.

An exemplary embodiment of the present application provides a quantum random number generator, as shown in fig. 1 and 2, which includes a light source 1, a beam splitter 2, a photodetector 3, a first signal amplifier 4, a second signal amplifier 5, a switching module 6, an analog-to-digital converter 7, and a processor 8, which are sequentially connected. The incident end of the beam splitter 2 is connected with the light source 1, the beam splitter 2 is used for dividing the light signal emitted by the light source 1 into multiple paths, the multiple photodetectors 3 are in one-to-one correspondence with the multiple paths of light signals to respectively capture the multiple paths of light signals, the photodetectors 3 generate current signals from the light signals, the first signal amplifier 4 converts the current signals into voltage signals and amplifies the voltage signals, the second signal amplifier 5 amplifies the voltage signals output by the first signal amplifier 4, the analog-to-digital converter 7 generates digital signals according to the amplified voltage signals, and the processor 8 generates quantum random numbers according to the digital signals.

In this embodiment, the quantum random number generator is further provided with a switching module 6, where the switching module 6 includes a switch 61 and a second-stage amplifying circuit, the input end of the switch 61 is connected to the output end of the second signal amplifier 5, the input end of the second-stage amplifying circuit is connected to the first output end of the switch 61, the output end of the second-stage amplifying circuit is connected to the input end of the analog-to-digital converter 7, the second output end of the switch 61 is connected to the input end of the analog-to-digital converter 7, and the switching module 6 is configured to switch the input end of the switch 61 between the first output end and the second output end of the switch 61.

So designed, after the second signal amplifier 5, the switching module 6 is arranged, the switching module 6 can switch and conduct the input end of the switching switch 61 with the first output end and the second output end of the switching switch 61 according to actual requirements, and when the switching module 6 switches on the input end of the switching switch 61 and the first output end of the switching switch 61, the voltage signal can be amplified again through the secondary amplifying circuit, so that the voltage signal input to the analog-to-digital converter 7 meets the signal use requirement, and the normal conversion of the analog-to-digital converter 7 is ensured. When the switching module 6 conducts the input end of the switching switch 61 and the second output end of the switching switch 61, the voltage signal output from the second signal amplifier 5 can directly enter the input end of the analog-to-digital converter 7, the voltage signal does not need to be amplified again, and saturation of the voltage signal is avoided while the voltage signal input to the analog-to-digital converter 7 meets the signal use requirement. The compatibility of the light source intensity is improved by arranging the switching module 6, so that the system stability of the quantum random number generator can be effectively improved.

For example, when the light source intensity is weaker, the voltage signal amplified by the second signal amplifier 5 still does not meet the signal use requirement, the switching module 6 conducts the input end of the switching switch 61 with the first output end of the switching switch 61, and amplifies the voltage signal amplified by the second signal amplifier 5 again through the secondary amplifying circuit, so that the voltage signal input to the analog-to-digital converter 7 meets the signal use requirement, and normal conversion of the analog-to-digital converter 7 is ensured. When the light source intensity is stronger, the voltage signal amplified by the second signal amplifier 5 meets the signal use requirement, the voltage signal does not need to be amplified again, the switching module 6 conducts the input end of the switching switch 61 and the second output end of the switching switch 61, and the voltage signal amplified by the second signal amplifier 5 is input to the analog-to-digital converter 7. For example, when the input terminal of the changeover switch 61 is switched to be conductive with a different output terminal, the changeover may be performed manually or may be performed automatically by the controller 62, which is not particularly limited.

In one embodiment, as shown in fig. 2, the second-stage amplifying circuit includes a first operational amplifier chip L1, an input end of the first operational amplifier chip L1 is connected to a first output end of the switch 61, and an output end of the first operational amplifier chip L1 is connected to an input end of the analog-to-digital converter 7. By adopting the arrangement mode, the voltage signal can be amplified again by the secondary amplifying circuit, so that the voltage signal input to the analog-to-digital converter 7 meets the signal use requirement, and the normal conversion of the analog-to-digital converter 7 is ensured.

In one embodiment, as shown in fig. 2, the quantum random number generator further includes a voltage sensor (not shown in the figure) and a controller 62, the voltage sensor is connected to the output end of the second signal amplifier 5, the magnitude of the voltage signal output by the second signal amplifier 5 is detected by the voltage sensor, and then the output end of the switch 61 is controlled by the controller 62 according to the detection result of the voltage sensor. Illustratively, the controller 62 controls the input terminal of the switch 61 to be conductive to the second output terminal of the switch 61 when the voltage signal detected by the voltage sensor does not satisfy the signal usage requirement, for example, the voltage signal exceeds a voltage range of-1V to +1v. When the voltage signal detected by the voltage sensor meets the signal usage requirement, for example, the voltage signal is in the voltage range of-1V to +1v, the controller 62 controls the input terminal of the switch 61 to be conducted with the first output terminal of the switch 61.

By adopting the design, the mode of manually switching the change-over switch 61 is replaced, the convenience and timeliness in switching can be effectively improved, and the system stability of the quantum random number generator is further improved.

In an embodiment, the plurality of photodetectors 3 each employ an avalanche photodiode with high detection sensitivity and low dark current, which is not only beneficial to capture of quantum signals, but also reduces complexity of post-processing.

In one embodiment, as shown in fig. 1 and 2, a plurality of photodetectors 3 are serially arranged to form a photodetection circuit 31, the first signal amplifier 4 includes an I-V conversion circuit 41 and an auto-zeroing circuit 42, an input terminal of the I-V conversion circuit 41 is connected to an output terminal of the photodetection circuit 31, and an output terminal of the I-V conversion circuit 41 is connected to an input terminal of the second signal amplifier 5. After the multiple optical signals respectively pass through the multiple photodetectors 3, the optical signals are converted into weak current signals, and the current signals are converted into voltage signals by the I-V conversion circuit 41, amplified and output to the second signal amplifier 5.

In this process, if the optical signal input to the photodetector circuit 31 is unbalanced, a comparative dc voltage is generated when converting the signal into a voltage signal, and the dc voltage is not useful for the quantum random number generator, but is likely to saturate the first signal amplifier 4, and thus needs to be filtered. In contrast, in the related art, an ac coupling mode of connecting capacitors in series after the signal amplifier is often adopted to eliminate the dc component, but the capacitors connected in series not only can cause signal quality deterioration, but also can form a low-pass filter with the resistor, so that the bandwidth and quality of the acquired signal are severely limited. In addition, the value of the potentiometer is manually adjusted to realize zero point adjustment in the related art, and the method is high in operation difficulty, high in technical requirements on operators, large in influence of human factors, and easy to receive interference of external vibration and other factors, so that the reliability of an optical signal acquisition result is low.

Based on this, in the present embodiment, as shown in fig. 2, the auto-zero circuit 42 is used to effectively filter the dc voltage. The auto-zeroing circuit 42 is used for integrating the output signal of the I-V conversion circuit 41, extracting the direct current component in the output signal of the I-V conversion circuit 41 and feeding back to the normal phase input end of the I-V conversion circuit 41, so as to effectively filter the direct current voltage generated by unbalance of the light source 1 and the device, avoid the influence of capacitive isolation on the voltage signal, replace the manual zeroing mode, reduce the operation difficulty, improve the reliability of the result of collecting the light signal, and effectively improve the system stability and reliability of the quantum random number generator.

In one embodiment, as shown in fig. 2, the auto-zeroing circuit 42 includes a second operational amplifier chip L2, a capacitor C, a first resistor R1 and a second resistor R2, two ends of the capacitor C are respectively connected to an inverting input end and an output end of the second operational amplifier chip L2, a non-inverting input end of the second operational amplifier chip L2 is grounded, an output end of the second operational amplifier chip L2 is connected to the non-inverting input end of the I-V conversion circuit 41 after being connected to the first resistor R1 in series, and an inverting input end of the second operational amplifier chip L2 is connected to the output end of the I-V conversion circuit 41 after being connected to the second resistor R2 in series, so as to receive an output signal of the I-V conversion circuit 41.

Illustratively, the second operational amplifier chip L2 may employ an operational amplifier chip LTC6268 with an extremely low bias current, and the bias current is of the fA level, so that the error of the operational amplifier chip itself may be effectively overcome.

In an embodiment, as shown in fig. 2, the I-V conversion circuit 41 includes a third operational amplifier chip L3, a third resistor R3 and a fourth resistor R4, two ends of the third resistor R3 are respectively connected with an inverting input end and an output end of the third operational amplifier chip L3, the inverting input end of the third operational amplifier chip L3 is connected with the output end of the photoelectric detection circuit 31, a non-inverting input end of the third operational amplifier chip L3 is connected with a first end of the fourth resistor R4, and a second end of the fourth resistor R4 is grounded.

The third operational amplifier chip L3 may also be an operational amplifier chip LTC6268 with an extremely low bias current, where the bias current is of the fA level, so that the error of the operational amplifier chip itself can be effectively overcome, and the I-V conversion circuit 41 is ensured to have a better balance characteristic.

In one embodiment, as shown in fig. 2, the second signal amplifier 5 includes a first-stage amplifying circuit 51, an input terminal of the first-stage amplifying circuit 51 is connected to an output terminal of the I-V conversion circuit 41, and an output terminal of the first-stage amplifying circuit 51 is connected to an input terminal of the switch 61. The voltage signal output by the I-V conversion circuit 41 is amplified by the second signal amplifier 5, so that the bandwidth and quality of the voltage signal are improved, thereby facilitating the normal conversion of the analog-to-digital converter 7.

In an embodiment, as shown in fig. 2, the first-stage amplifying circuit 51 includes a fourth operational amplifier chip L4, a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7, the fifth resistor R5 is serially connected between the output end of the I-V conversion circuit 41 and the inverting input end of the fourth operational amplifier chip L4, two ends of the sixth resistor R6 are respectively connected to the inverting input end and the output end of the fourth operational amplifier chip L4, and the non-inverting input end of the fourth operational amplifier chip L4 is serially connected to the seventh resistor R7 and then grounded. The effective voltage signal output by the I-V conversion circuit 41 and filtered by the auto-zeroing circuit 42 to useless DC voltage is amplified by R6/R5 times by the primary amplifying circuit 51 and then output to the switching module 6.

In one embodiment, as shown in fig. 1 and 2, the beam splitter 2 splits the optical signal emitted by the light source 1 into two paths, the plurality of photodetectors 3 includes a first photodetector D1 and a second photodetector D2 that are arranged in series, the negative electrode of the first photodetector D1 is connected to a positive voltage, the positive electrode of the first photodetector D1 is connected to the input end of the I-V conversion circuit 41, the positive electrode of the second photodetector D2 is connected to a negative voltage, and the negative electrode of the second photodetector D2 is connected to the positive electrode of the first photodetector D1. The first photoelectric detector D1 and the second photoelectric detector D2 both adopt avalanche photodiodes, which is not only beneficial to capturing optical signals, but also can carry out preliminary amplification on the optical signals, thereby reducing the complexity of post-processing.

In practical applications, two optical signals from the light source 1 enter the photo-detection circuit 31, and the first photo-detector D1 and the second photo-detector D2 act to generate current signals I11 and I12, and the current flows as indicated by arrows in fig. 2. The dc components in I11 and I12 are unwanted signals to the quantum random number generator, and theoretically, the dc components can be offset by the balancing action of the photodetector circuit 31, so that an effective ac signal i2=i11+i12 can be obtained, and then the ac signal I2 is converted by the I-V conversion circuit 41 to obtain a voltage signal u1=i3×r3, i3=i2. However, in general, the optical signals of the optical path 1 and the optical path 2 cannot be completely consistent, and the performances of the first photodetector D1 and the second photodetector D2 are also deviated, so that the dc components of I11 and I12 cannot be completely cancelled, and thus, a useless dc voltage U1' is obtained after the signal is converted by the I-V conversion circuit 41. The automatic zero setting circuit 42 composed of the second operational amplifier chip L2, the capacitor C, the first resistor R1 and the second resistor R2 extracts the dc voltage U1' and feeds back the dc voltage U1' to the non-inverting input terminal of the third operational amplifier chip L3 for elimination, so that the signal output by the I-V conversion circuit 41 is an effective voltage signal u=i3×r3-U1'. The first-stage amplifying circuit 51 amplifies U by a factor of R6/R5 and outputs the amplified U to the switching module 6.

In the quantum random number generator provided by the embodiment of the application, the photoelectric detector adopts the avalanche photodiode, which is not only beneficial to capturing of optical signals, but also capable of carrying out preliminary amplification on the captured optical signals, so that the complexity of post-processing can be reduced.

By arranging the automatic zeroing circuit 42 in the first signal amplifier 4, the direct-current voltage is filtered out to replace a manual zeroing mode, the operation difficulty is reduced, the reliability of the result of collecting the optical signals is improved, and the system stability and reliability of the quantum random number generator are effectively improved.

After the second signal amplifier 5, a switching module 6 is arranged, the switching module 6 can switch and conduct the input end of the switching switch 61 with the first output end and the second output end of the switching switch 61 according to actual requirements, and when the switching module 6 switches on the input end of the switching switch 61 and the first output end of the switching switch 61, the voltage signal can be amplified again through the second-stage amplifying circuit, so that the voltage signal input to the analog-digital converter 7 meets the signal use requirement, and normal conversion of the analog-digital converter 7 is ensured. When the switching module 6 conducts the input end of the switching switch 61 and the second output end of the switching switch 61, the voltage signal output from the second signal amplifier 5 can directly enter the input end of the analog-to-digital converter 7, the voltage signal does not need to be amplified again, and saturation of the voltage signal is avoided while the voltage signal input to the analog-to-digital converter 7 meets the signal use requirement. The compatibility of the light source intensity is improved by arranging the switching module 6, and the intensity of the amplified voltage signal is ensured to be in a proper range, so that the system stability of the quantum random number generator can be effectively improved.

The above description may be implemented alone or in various combinations and these variants are all within the scope of the present application.

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and are not limiting. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the corresponding technical solutions.

Claims

1. The quantum random number generator is characterized by comprising a light source, a beam splitter, a plurality of photoelectric detectors, a first signal amplifier, a second signal amplifier, a switching module, an analog-to-digital converter and a processor which are connected in sequence; the incident end of the beam splitter is connected with the light source, the beam splitter is used for dividing the light signals emitted by the light source into multiple paths, the multiple photoelectric detectors are in one-to-one correspondence with the multiple paths of light signals, the photoelectric detectors are used for generating current signals from the light signals, the first signal amplifier is used for converting the current signals into voltage signals and amplifying the voltage signals, the second signal amplifier is used for amplifying the voltage signals output by the first signal amplifier, the analog-to-digital converter is used for generating digital signals according to the amplified voltage signals, and the processor is used for generating quantum random numbers according to the digital signals;

2. The quantum random number generator of claim 1, wherein the secondary amplification circuit comprises a first op-amp chip, an input of the first op-amp chip is connected to a first output of the switch, and an output of the first op-amp chip is connected to an input of the analog-to-digital converter.

3. The quantum random number generator of claim 1, wherein the quantum random number generator further comprises:

the voltage sensor is connected to the output end of the second signal amplifier and is used for detecting the magnitude of a voltage signal output by the second signal amplifier;

and the controller is configured to control the output end of the switching switch to be switched according to the detection result of the voltage sensor.

4. The quantum random number generator of claim 1, wherein the plurality of photodetectors are each avalanche photodiodes.

5. The quantum random number generator of any one of claims 1 to 4, wherein the plurality of photodetectors are arranged in series to form a photodetector circuit, the first signal amplifier comprising:

the input end of the I-V conversion circuit is connected with the output end of the photoelectric detection circuit, the output end of the I-V conversion circuit is connected with the input end of the second signal amplifier, and the I-V conversion circuit is used for converting the current signal into a voltage signal and amplifying the voltage signal;

and the automatic zero setting circuit is used for integrating the output signal of the I-V conversion circuit, extracting the direct current component in the output signal of the I-V conversion circuit and feeding back the direct current component to the non-inverting input end of the I-V conversion circuit.

6. The quantum random number generator of claim 5, wherein the auto-zeroing circuit comprises a second operational amplifier chip, a capacitor, a first resistor and a second resistor, wherein two ends of the capacitor are respectively connected with an inverting input end and an output end of the second operational amplifier chip, a non-inverting input end of the second operational amplifier chip is grounded, an output end of the second operational amplifier chip is connected with the first resistor in series and then is connected with a non-inverting input end of the I-V conversion circuit, and an inverting input end of the second operational amplifier chip is connected with the second resistor in series and then is connected with an output end of the I-V conversion circuit.

7. The quantum random number generator of claim 5, wherein the I-V conversion comprises a third operational amplifier chip, a third resistor and a fourth resistor, wherein two ends of the third resistor are respectively connected with an inverting input end and an output end of the third operational amplifier chip, the inverting input end of the third operational amplifier chip is connected with the output end of the photoelectric detection circuit, the non-inverting input end of the third operational amplifier chip is connected with the first end of the fourth resistor, and the second end of the fourth resistor is grounded.

8. The quantum random number generator of claim 5, wherein the second signal amplifier comprises a primary amplifying circuit, an input of the primary amplifying circuit is connected to an output of the I-V conversion circuit, and an output of the primary amplifying circuit is connected to an input of the switch.

9. The quantum random number generator of claim 8, wherein the primary amplifying circuit comprises a fourth operational amplifier chip, a fifth resistor, a sixth resistor and a seventh resistor, the fifth resistor is serially arranged between the output end of the I-V conversion circuit and the inverting input end of the fourth operational amplifier chip, two ends of the sixth resistor are respectively connected with the inverting input end and the output end of the fourth operational amplifier chip, and the non-inverting input end of the fourth operational amplifier chip is serially connected with the seventh resistor and then grounded.

10. The quantum random number generator of claim 5, wherein the beam splitter splits an optical signal emitted by the light source into two paths, the plurality of photodetectors comprises a first photodetector and a second photodetector arranged in series, a negative electrode of the first photodetector is connected with a positive voltage, a positive electrode of the first photodetector is connected with an input end of the I-V conversion circuit, a positive electrode of the second photodetector is connected with a negative voltage, and a negative electrode of the second photodetector is connected with a positive electrode of the first photodetector.